This invention relates to building ventilators and more particularly ridge ventilators of the type in which an elongated ventilator structure is mounted over an elongated opening in the roof of the building along the ridge line. Many different kinds of such ventilators are known and used in industry. Some are the stationary type relying entirely on the prevailing breezes and the higher temperature of the air or fumes to be evacuated to create negative pressure within the ventilator and to provide the forces necessary to effect the exhaust. Others are provided with auxilliary means such as electric fans or blowers to assist in the exhaust process.
Ridge ventilators of these general types have long been known. See for example the ventilators illustrated and described in U.S. Pat. Nos. 2,232,027; 2,410,950; 3,213,770; and British Pat. No. 865,730. These and U.S. Pat. No. 2,232,027 which was assigned to the present assignee company disclose ridge ventilators which rely on air movement to provide the power. The ventilators have several disadvantages when used on certain types of buildings. Most of them are open at the top and to prevent rain, snow and sleet from entering the building they are provided with damper means to be operated, usually manually, to block the roof opening. Obviously, no ventilation can take place during such periods.
The ridge ventilator of U.S. Pat. No. 2,232,027 has a large rectangular opening at the top protected only by a bird proof screen, and can, during a heavy snow, become partially clogged, at least to the point of interfering with the operation of the adjustable movable damper used for controlling the ventilation. Moreover, such a ventilator is of somewhat complicated construction which renders it more difficult to build and to assemble on the building.
In the building ventilator art, little attention has been given to providing a simple and effective ridge ventilator for agricultural barns and other farm buildings. The present invention is particularly suitable for such buildings and should prove beneficial to the Post Frame Industry for that reason. For those not familiar with such terms, it may be explained that originally, at least in this country, cattle and horse barns were simply constructed of poles or upright timbers sunk into the ground, and provided with sidings and a roof. In more modern times the pole timbers have been squared and finished before use. The industry which provides such has come to be known as the Post Frame Industry.
Sometimes such farm barns have been provided with a single cupola ventilator perched in the middle of the barn roof at the ridge. Such cupola ventilators however have not proved adequate, particularly for barn structures which are provided with a loft for storing grain, hay or the like. Moreover, in such structures it is highly desirable to ventilate the loft areas particularly under the eaves of the roof in order to keep the material being stored and also the insulation dry. For such structures it is not essential, nor is it desirous for the ventilator to be provided with auxilliary means such as fans to assist in the exhaust process. But it is important that a reasonable amount of negative pressure be developed and that the exhaust action extend substantially from one end of the roof to the other.
It has been desirous for some years to provide a stationary ridge ventilator for barn structures and the like which, while overcoming these disadvantages, at the same time is efficient and quiet in operation (with no wind rattling) and which is easy to manufacture and easy to assemble and erect on a roof even for inexperienced workmen. Moreover, such ventilators should be entirely weatherproof and clog-proof and of low streamline, cleanline, appearance and operable under all conditions without the necessity of additional fans or other exhaust means. It is a general object of this invention to provide such a ventilator.